Method for producing fireproof materials based on sodium silicate

Abstract

The present invention concerns a process for the production of a solid fire protection material. The composition for producing the fire protection material contains at least one water glass and microcapsules provided with propellant gas. The fire protection material is formed by expanding the microcapsules or by breaking the polymer material of the shell of the microcapsules by the influence of temperature or by adding an agent which breaks the shell of the microcapsules.

The invention claimed is: 
     
       1. A process for producing a solid fire protection material, the process comprising:
 (1) providing a composition comprising at least one water glass and at least one propellant-provided microcapsule having a propellant-provided core and a polymer material as a shell, wherein the microcapsules comprise at least 20 wt. % propellant, based on dry weight; and 
 (2) contacting the microcapsules with (a) a swelling agent comprising propylene carbonate or (b) a shell breaking agent comprising propylene carbonate in order to swell the microcapsules and/or break the polymer material of the shell of the microcapsules. 
 
     
     
       2. The process according to  claim 1 , wherein the mass ratio between the at least one water glass and the at least one microcapsule provided with the propellant is from 5.0 to 30.0. 
     
     
       3. The process according to  claim 1 , wherein the polymer material is selected from the group consisting of copolymers, copolymers of acrylonitrile, methacrylate and/or acrylate, vinylidene chloride copolymers and vinylidene chloride-acrylonitrile copolymers. 
     
     
       4. The process according to  claim 1 , wherein the at least one water glass comprises at least one potassium water glass. 
     
     
       5. The process according to  claim 1 , wherein a propellant release of the composition takes place after the addition of a shell-breaking agent in a timeframe of 20 seconds to 20 minutes. 
     
     
       6. The process according to  claim 1 , wherein the composition further comprises at least one of (a) at least one component supporting the ceramization of the composition at elevated temperatures; and (b) at least one organic fibre. 
     
     
       7. The process according to  claim 6 , wherein the at least one component that supports the ceramization at elevated temperatures is present and is selected from the group consisting of mineral additives, aluminium hydroxide, filter dust, fly ash, ceramic hollow spheres, hollow glass spheres, foam glass granules, slate flour, quartz flour, mica, wollastonite, calcium carbonates, kaolin, vermiculite and ettringite. 
     
     
       8. The process according to  claim 6 , wherein the at least one organic fibre is present and is selected from the group consisting of polyalkylene fibres, polyethylene fibres, polypropylene fibres; acrylic fibres: aramid fibres; polyamide fibres, polyhexamethylene diadipamide fibres, polycaprolactam fibres, aromatic polyamide fibres, partially aromatic polyamide fibres; partially aromatic polyester fibres, and wholly aromatic polyester fibres. 
     
     
       9. The process according to  claim 1 , wherein the solid fire protection material is in the shape of a fire protection panel. 
     
     
       10. The process according to  claim 1 , wherein the composition further comprises at least one of:
 (1) at least one component which leads to hardening and/or binding of the composition; 
 (2) at least one component which has a moisture-retaining and/or hygroscopic property; and 
 (3) at least one silicic acid. 
 
     
     
       11. The process according to  claim 1 , wherein the fire protection material obtained has a density of less than 0.6 g/cm 3 . 
     
     
       12. The process according to  claim 1 , wherein the propellant comprises a propellant gas selected from the group consisting of hydrocarbons, methane, ethane, propane, n-butane, isobutane, pentanes, n-pentane, iso-pentane, neopentane; chlorofluorocarbons, trichlorofluoromethane, dichlorodifluoromethane; dimethyl ether; carbon dioxide, nitrogen, air, and mixtures thereof. 
     
     
       13. A composite material, the composite material comprising:
 the fire protection material obtained according to  claim 1 , and 
 at least one carrier material. 
 
     
     
       14. The composite material according to  claim 13 , wherein the at least one carrier material is selected from the group consisting of non-woven materials; paper materials and cardboard materials, paper honeycombs; plastic materials; metal materials, metal foils, aluminium foils; glass materials, glass foils, glass wool; cotton fabrics; wood materials; mineral wool; materials of extruded polystyrene foam, polyurethane foam, polyethylene foam and polypropylene foam; materials of jute, flax, hemp and cellulose fibres; and textile materials. 
     
     
       15. The composite material according to  claim 13 , wherein the fire protection material is in the form of plates, cuboidal bodies, bricks, concave or convex bodies or tubular bodies. 
     
     
       16. The composite material according to  claim 13 , further comprising at least one layer applied to the at least one carrier material. 
     
     
       17. The composite material according to  claim 16 , wherein the at least one layer is selected from the group consisting of an aluminium foil, a glass fleece, a paper, and cardboard material. 
     
     
       18. A composite material, the composite material comprising:
 (1) a first layer selected from the group consisting of an aluminium foil, a glass fleece, a paper, a cardboard material, and a composite thereof; 
 (2) a second layer selected from the group consisting of fleece materials; paper materials and cardboard materials, paper honeycomb; plastic materials; metal materials, metal foils, aluminium foils; glass materials, glass foils and glass wool; cotton fabrics; wood materials; mineral wool; materials made of extruded polystyrene foam, polyurethane foam, polyethylene foam and polypropylene foam; materials made of jute, flax, hemp and cellulose fibres; and textile materials; and 
 (3) a third layer selected from the group consisting of an aluminium foil, a glass fleece, a paper, a cardboard material, and a composite thereof; 
 
       wherein the composite material is constructed such that that the first layer is provided on a first side of the second layer and the third layer is provided on a second side of the second layer and the fire protection material obtained according  claim 16  is provided on one or both sides of the second layer. 
     
     
       19. A fire protection material, the fire protection material comprising:
 the composition according to (1) or (1′) of  claim 1 , and 
 at least one carrier material, 
 wherein the composition is either applied to the at least one carrier material, or the at least one carrier material is impregnated with the composition. 
 
     
     
       20. A method of protecting from fire or heat a surface, structure or object, selected from the group consisting of doors, walls, floors, ceilings, openings, penetrations, tunnels, tubes, ships, vehicles, wagons, containers, cables, electronics, personal protective clothing, furnaces, the method comprising applying to the surface structure or object, fire protection material of  claim 1 . 
     
     
       21. The process of  claim 1 , wherein swelling the microcapsules and/or breaking the polymer material of the shell of the microcapsules by the addition of propylene carbonate is effected at ambient temperature, without the application of heat. 
     
     
       22. The process of  claim 1 , wherein one sodium silicate glass is present, and wherein a weight ratio of SiO 2  to Na 2 O is within the range of 2.3 to 3.8. 
     
     
       23. The process of  claim 22 , wherein a density of the solid fire protection material is within the range of 1300 to 1600 kg/m 3 . 
     
     
       24. The process of  claim 22 , wherein a water content of the solid fire protection material is within the range of 50 to 70 wt. %. 
     
     
       25. The process of  claim 1 , wherein the composition comprises at least two different sodium silicate glasses, the first sodium silicate glass having a viscosity of 1000 to 2400 mPa*s (20° C.) and the second sodium silicate glass having a viscosity of 75 to 250 mPa*s (20° C.). 
     
     
       26. The process of  claim 25 , wherein the first sodium silicate glass has at least one other of the following properties:
 (1) weight ratio of SO 2  to Na 2 O within the range of 2.3 to 2.6; and/or 
 (2) density within the range of 1500 to 1600 kg/m 3 ; and/or 
 (3) water content within the range of 50 to 55 wt. %. 
 
     
     
       27. The process of  claim 25 , wherein the second sodium silicate glass has at least one of the following characteristics:
 (1) weight ratio of SiO 2  to Na 2 O, within the range of 2.8 to 3.8; and/or 
 (2) density within the range of 1300 to 1500 kg/m 3 .